Abstract
We demonstrate a thermodynamic state change dominated by a non-thermodynamic variable found in the Ni3 Al0.45 V0.50 alloy. Specifically, the L12→L12+D022 evolution, which is a sub-phenomenon of the fcc→L12+D022 phase transition, takes place only when lattice defects are introduced to more than a certain critical density in the L12 diffusion field. Because the defect density changes along with the variation in the thermodynamic path, the path variation can alter the evolved state even under an identical thermodynamic condition. This path dependence of the state change shows the non-deterministic (chaotic) nature of the phase transition.